HYDROSTATIC MEASUREMENTS FOR

Hydrostatic pressure refers to the pressure exerted by a liquid at rest. Groundwater exerts hydrostatic pressure on the surrounding soil, and rock formations can be used to measure groundwater levels. Keller has a range of products for groundwater.

The pressure of the water increases with depth, so the deeper the water, the higher the hydrostatic pressure. Therefore, by measuring the hydrostatic pressure at a specific point in the ground, it is possible to determine the depth of the water table at that location. Hydrostatic pressure is also used for the fluid column measurement of storage water tanks. It gives insight in the actual volume, and when measurements are stored, it gives insight in consumption data, and thus remaining stock, as well.

Overall, hydrostatic pressure is a valuable tool for measuring groundwater levels, and it is used extensively by hydrologists, geologists and other scientists to monitor and manage groundwater resources.

When monitoring groundwater, the measuring points may be relatively far away and difficult to reach. For these applications, Keller has solutions involving level loggers via short-range radio interfaces as well as level loggers with a remote data transmission unit via the Global System for Mobile Communication (GSM) or the internet.

Kolibri Cloud/desktop is used to process, analyse and prepare the collected data. Keller provides the following products:

• Level probes – With a special design and cable and housing materials that have been chosen for compatibility with their surroundings, these submersible probes can be used in a wide range of liquids for level and fill management. a saying that is increasingly relevant to South Africa’s groundwater resources. In a dry country such as South Africa, adequate information on the status and trends of groundwater resources is paramount for strategic development. A groundwater app could be the answer.

• Data loggers – A variety of data logger designs for recording pressure and temperature profiles. Depending on the system, the data is read out via a plug connection or remote transfer.

• Multiparameter data loggers (DCX22-CTD) measure conductivity and temperature as well as pressure, along with the depth of bodies of water. The integrated Pt1000 achieves an accuracy of ±0.1°C, and the conductivity can be measured at ±2.5% of the selected range (0.2/2/20/200 mS/cm). Thanks to their long-life battery, they can keep recording measurement results for years (up to 10 years at a rate of one measurement per hour). The logger can be configured using the supplied software (measurement interval, incident management, delayed measurement starts) and data that has been read can be displayed in a graph or chart, corrected using air pressure values, converted into fill levels or other units, and exported.

• Kolibri Cloud is a web application for collecting and displaying measured values that are recorded by Keller IoT devices and transmitted via mobile radio or LoRaWAN. Kolibri Cloud offers a wide variety of options for device configuration and displays current measured values and logger recordings in graph form. Thanks to the search and filter options, saved measurement data can be organised with ease and can also be exported as an image, as an Excel or Word report, or in additional formats. Existing software solutions can be used to access data in Kolibri Cloud via JSON API. All products in the Kolibri suite are intercompatible and can exchange data with one another. The functions are continually being further expanded and optimised.